The present invention relates to a preceding vehicle follow-up control system for enabling a controlled vehicle to recognize a preceding vehicle and to follow up the preceding vehicle while keeping a vehicle-to-vehicle distance.
Japanese Patent Provisional Publication No. 10-114237 has disclosed a conventional follow-up control system which is arranged to cancel a follow-up control according to an accelerating condition of the controlled vehicle.
Although this conventional preceding vehicle follow-up control system is basically arranged to stop the follow-up control when a difference between the throttle opening detected value and the throttle opening estimate becomes greater than a threshold, it is arranged to automatically resume the follow-up control when an accelerator pedal is released. This arrangement yet includes problems to be improved in drive feeling.
It is therefore an object of the present invention to provide a preceding vehicle follow-up control system which smoothly resume a follow-up control after canceling the follow-up control during an acceleration based on a driver""s demand.
A preceding vehicle follow-up control system according to the present invention is for a vehicle and comprises a vehicle-to-vehicle distance detector, a vehicle speed detector, an accelerating operation detector and a controller connected thereto. The vehicle-to-vehicle distance detector detects a distance between a controlled vehicle and a preceding vehicle and outputs a signal indicative of the vehicle-to-vehicle distance. The vehicle speed detector that detects a vehicle speed of the controlled vehicle and outputs a signal indicative of the controlled-vehicle speed. The accelerating operation detector that detects whether an accelerating operation based on a driver""s demand is executed. The controller is arranged to calculate a target vehicle speed employed for bringing the vehicle-to-vehicle distance closer to a target vehicle-to-distance on the basis of the vehicle-to-vehicle distance and the controlled-vehicle speed, to control the controlled-vehicle speed to bring the controlled-vehicle speed closer to the target vehicle speed, to detect whether the controlled-vehicle speed is greater than a control continuation decision value which is greater than an upper limit of a settable range of a set vehicle speed, to decelerate the controlled-vehicle speed to the set vehicle speed at a rate of a preset deceleration when the controlled-vehicle speed is greater than the control continuation decision value and when the accelerating operation is not executed.